From 3554116d3aae25353713f3d0131d86ae6c1e5674 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Wed, 8 Jan 2014 09:49:01 -0500 Subject: [PATCH] nfsd4: simplify xdr encoding of nfsv4 names We can simplify the idmapping code if it does its own encoding and returns nfs errors. Signed-off-by: J. Bruce Fields --- fs/nfsd/acl.h | 2 +- fs/nfsd/idmap.h | 4 ++-- fs/nfsd/nfs4acl.c | 20 +++++++++++------ fs/nfsd/nfs4idmap.c | 50 ++++++++++++++++++++++++++++--------------- fs/nfsd/nfs4xdr.c | 52 ++++++--------------------------------------- 5 files changed, 55 insertions(+), 73 deletions(-) diff --git a/fs/nfsd/acl.h b/fs/nfsd/acl.h index 8b186a4955cc..afd3e0eae642 100644 --- a/fs/nfsd/acl.h +++ b/fs/nfsd/acl.h @@ -43,7 +43,7 @@ struct nfs4_acl *nfs4_acl_new(int); int nfs4_acl_get_whotype(char *, u32); -int nfs4_acl_write_who(int who, char *p); +__be32 nfs4_acl_write_who(int who, __be32 **p, int *len); #define NFS4_ACL_TYPE_DEFAULT 0x01 #define NFS4_ACL_DIR 0x02 diff --git a/fs/nfsd/idmap.h b/fs/nfsd/idmap.h index bf95f6b817a4..66e58db01936 100644 --- a/fs/nfsd/idmap.h +++ b/fs/nfsd/idmap.h @@ -56,7 +56,7 @@ static inline void nfsd_idmap_shutdown(struct net *net) __be32 nfsd_map_name_to_uid(struct svc_rqst *, const char *, size_t, kuid_t *); __be32 nfsd_map_name_to_gid(struct svc_rqst *, const char *, size_t, kgid_t *); -int nfsd_map_uid_to_name(struct svc_rqst *, kuid_t, char *); -int nfsd_map_gid_to_name(struct svc_rqst *, kgid_t, char *); +__be32 nfsd4_encode_user(struct svc_rqst *, kuid_t, __be32 **, int *); +__be32 nfsd4_encode_group(struct svc_rqst *, kgid_t, __be32 **, int *); #endif /* LINUX_NFSD_IDMAP_H */ diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c index 8a50b3c18093..eea24c9a561d 100644 --- a/fs/nfsd/nfs4acl.c +++ b/fs/nfsd/nfs4acl.c @@ -37,6 +37,7 @@ #include #include #include +#include "nfsd.h" #include "acl.h" @@ -848,18 +849,23 @@ nfs4_acl_get_whotype(char *p, u32 len) return NFS4_ACL_WHO_NAMED; } -int -nfs4_acl_write_who(int who, char *p) +__be32 nfs4_acl_write_who(int who, __be32 **p, int *len) { int i; + int bytes; for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { - if (s2t_map[i].type == who) { - memcpy(p, s2t_map[i].string, s2t_map[i].stringlen); - return s2t_map[i].stringlen; - } + if (s2t_map[i].type != who) + continue; + bytes = 4 + (XDR_QUADLEN(s2t_map[i].stringlen) << 2); + if (bytes > *len) + return nfserr_resource; + *p = xdr_encode_opaque(*p, s2t_map[i].string, + s2t_map[i].stringlen); + *len -= bytes; + return 0; } - BUG(); + WARN_ON_ONCE(1); return -1; } diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c index 4832fd819f88..c0dfde68742e 100644 --- a/fs/nfsd/nfs4idmap.c +++ b/fs/nfsd/nfs4idmap.c @@ -551,27 +551,46 @@ idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen return 0; } -static int -idmap_id_to_name(struct svc_rqst *rqstp, int type, u32 id, char *name) +static __be32 encode_ascii_id(u32 id, __be32 **p, int *buflen) +{ + char buf[11]; + int len; + int bytes; + + len = sprintf(buf, "%u", id); + bytes = 4 + (XDR_QUADLEN(len) << 2); + if (bytes > *buflen) + return nfserr_resource; + *p = xdr_encode_opaque(*p, buf, len); + *buflen -= bytes; + return 0; +} + +static __be32 idmap_id_to_name(struct svc_rqst *rqstp, int type, u32 id, __be32 **p, int *buflen) { struct ent *item, key = { .id = id, .type = type, }; int ret; + int bytes; struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname)); ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item); if (ret == -ENOENT) - return sprintf(name, "%u", id); + return encode_ascii_id(id, p, buflen); if (ret) - return ret; + return nfserrno(ret); ret = strlen(item->name); - BUG_ON(ret > IDMAP_NAMESZ); - memcpy(name, item->name, ret); + WARN_ON_ONCE(ret > IDMAP_NAMESZ); + bytes = 4 + (XDR_QUADLEN(ret) << 2); + if (bytes > *buflen) + return nfserr_resource; + *p = xdr_encode_opaque(*p, item->name, ret); + *buflen -= bytes; cache_put(&item->h, nn->idtoname_cache); - return ret; + return 0; } static bool @@ -603,12 +622,11 @@ do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u return idmap_name_to_id(rqstp, type, name, namelen, id); } -static int -do_id_to_name(struct svc_rqst *rqstp, int type, u32 id, char *name) +static __be32 encode_name_from_id(struct svc_rqst *rqstp, int type, u32 id, __be32 **p, int *buflen) { if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS) - return sprintf(name, "%u", id); - return idmap_id_to_name(rqstp, type, id, name); + return encode_ascii_id(id, p, buflen); + return idmap_id_to_name(rqstp, type, id, p, buflen); } __be32 @@ -637,16 +655,14 @@ nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen, return status; } -int -nfsd_map_uid_to_name(struct svc_rqst *rqstp, kuid_t uid, char *name) +__be32 nfsd4_encode_user(struct svc_rqst *rqstp, kuid_t uid, __be32 **p, int *buflen) { u32 id = from_kuid(&init_user_ns, uid); - return do_id_to_name(rqstp, IDMAP_TYPE_USER, id, name); + return encode_name_from_id(rqstp, IDMAP_TYPE_USER, id, p, buflen); } -int -nfsd_map_gid_to_name(struct svc_rqst *rqstp, kgid_t gid, char *name) +__be32 nfsd4_encode_group(struct svc_rqst *rqstp, kgid_t gid, __be32 **p, int *buflen) { u32 id = from_kgid(&init_user_ns, gid); - return do_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name); + return encode_name_from_id(rqstp, IDMAP_TYPE_GROUP, id, p, buflen); } diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 67b44963e8ad..8198ecf3c03a 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -1965,56 +1965,16 @@ static u32 nfs4_file_type(umode_t mode) }; } -static __be32 -nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, kuid_t uid, kgid_t gid, - __be32 **p, int *buflen) -{ - int status; - - if (*buflen < (XDR_QUADLEN(IDMAP_NAMESZ) << 2) + 4) - return nfserr_resource; - if (whotype != NFS4_ACL_WHO_NAMED) - status = nfs4_acl_write_who(whotype, (u8 *)(*p + 1)); - else if (gid_valid(gid)) - status = nfsd_map_gid_to_name(rqstp, gid, (u8 *)(*p + 1)); - else - status = nfsd_map_uid_to_name(rqstp, uid, (u8 *)(*p + 1)); - if (status < 0) - return nfserrno(status); - *p = xdr_encode_opaque(*p, NULL, status); - *buflen -= (XDR_QUADLEN(status) << 2) + 4; - BUG_ON(*buflen < 0); - return 0; -} - -static inline __be32 -nfsd4_encode_user(struct svc_rqst *rqstp, kuid_t user, __be32 **p, int *buflen) -{ - return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, user, INVALID_GID, - p, buflen); -} - -static inline __be32 -nfsd4_encode_group(struct svc_rqst *rqstp, kgid_t group, __be32 **p, int *buflen) -{ - return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, INVALID_UID, group, - p, buflen); -} - static inline __be32 nfsd4_encode_aclname(struct svc_rqst *rqstp, struct nfs4_ace *ace, __be32 **p, int *buflen) { - kuid_t uid = INVALID_UID; - kgid_t gid = INVALID_GID; - - if (ace->whotype == NFS4_ACL_WHO_NAMED) { - if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP) - gid = ace->who_gid; - else - uid = ace->who_uid; - } - return nfsd4_encode_name(rqstp, ace->whotype, uid, gid, p, buflen); + if (ace->whotype != NFS4_ACL_WHO_NAMED) + return nfs4_acl_write_who(ace->whotype, p, buflen); + else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP) + return nfsd4_encode_group(rqstp, ace->who_gid, p, buflen); + else + return nfsd4_encode_user(rqstp, ace->who_uid, p, buflen); } #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \ -- 2.39.5